Embedding of Countable Orders in Turing Degrees
Matematičeskie zametki, Tome 72 (2002) no. 5, pp. 682-687.

Voir la notice de l'article provenant de la source Math-Net.Ru

In their classical papers, Lerman, Lachlan, and Lebeuf developed the embedding method, which provides constructions of initial segments of Turing degrees isomorphic to various partially ordered structures. We analyze this method and prove that there is a nonzero degree below each decreasing chain of degrees uniform in $\mathbf 0'$. This imposes restrictions on the application of the embedding method.
@article{MZM_2002_72_5_a5,
     author = {Sh. T. Ishmukhametov},
     title = {Embedding of {Countable} {Orders} in {Turing} {Degrees}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {682--687},
     publisher = {mathdoc},
     volume = {72},
     number = {5},
     year = {2002},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2002_72_5_a5/}
}
TY  - JOUR
AU  - Sh. T. Ishmukhametov
TI  - Embedding of Countable Orders in Turing Degrees
JO  - Matematičeskie zametki
PY  - 2002
SP  - 682
EP  - 687
VL  - 72
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MZM_2002_72_5_a5/
LA  - ru
ID  - MZM_2002_72_5_a5
ER  - 
%0 Journal Article
%A Sh. T. Ishmukhametov
%T Embedding of Countable Orders in Turing Degrees
%J Matematičeskie zametki
%D 2002
%P 682-687
%V 72
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MZM_2002_72_5_a5/
%G ru
%F MZM_2002_72_5_a5
Sh. T. Ishmukhametov. Embedding of Countable Orders in Turing Degrees. Matematičeskie zametki, Tome 72 (2002) no. 5, pp. 682-687. http://geodesic.mathdoc.fr/item/MZM_2002_72_5_a5/

[1] Spector C., “On degrees of recursive unsolvability”, Ann. of Math., 64 (1956), 581–592 | DOI | MR | Zbl

[2] Shoenfield J. R., “A theorem on minimal degrees”, J. Symbolic Logic, 31 (1966), 539–544 | DOI | MR | Zbl

[3] Titgemeyer D., “Untersuchungen über die Struktur des Kleene-Postchen Halbverbandes des Grade der Rekursivenunlösbarkeit”, Arch. Math. Logik Grundlagenforsch, 8:1–2 (1962), 45–62 | MR

[4] Hugill D. F., “Initial segments of Turing degrees”, Proc. London Math. Soc., 19 (1969), 1–16 | DOI | MR | Zbl

[5] Lerman M., “Some nondistributive lattices as initial segments of the degrees of unsolvability”, J. Symbolic Logic, 34 (1969), 85–98 | DOI | MR | Zbl

[6] Lerman M., “Initial segments of the degrees of unsolvability”, Ann. Math., 93 (1971), 365–389 | DOI | MR | Zbl

[7] Lachlan A. H., Lebeuf R., “Countable initial segments of the degrees of unsolvability”, J. Symbolic Logic, 41 (1976), 289–300 | DOI | MR | Zbl

[8] Lerman M., Degrees of Unsolvability, Perspectives in Mathematical Logic. Omega Series, Springer-Verlag, Berlin–Heidelberg–London–New York–Tokyo, 1983 | Zbl

[9] Soar R. I., Vychislimo perechislimye mnozhestva i stepeni, Kazan, 2000

[10] Odifreddi P., Classical Recursion Theory, Studies in Logic and the Foundations of Mathematics, 125, North-Holland, Amsterdam–New York–Oxford–Tokyo, 1989 | MR | Zbl